Dishwashing agents are available to consumers in a large number of presentation forms. In addition to the traditional liquid hand dishwashing agents, automatic dishwashing agents especially have particular significance now that household automatic dishwashers are widespread. These automatic dishwashing agents are offered to the consumer typically in solid form, for example as powders or tablets, but increasingly also in liquid form. Emphasis has for some time been placed principally on convenient dispensing of washing and cleaning agents, and on simplification of the working steps necessary for carrying out a washing or cleaning method.
Furthermore, one of the main objectives of manufacturers of automatic cleaning agents is to improve the cleaning performance of these agents, increased attention recently having been paid to cleaning performance in low-temperature cleaning cycles or in cleaning cycles having reduced water consumption. To this end, new ingredients, for example more-effective surfactants, polymers, enzymes or bleaching agents, have preferably been added to the cleaning agents. Because new ingredients are available only to a limited extent, however, and because for environmental and economic reasons the quantity of the ingredients used for each cleaning cycle cannot be arbitrarily increased, there are natural limits to this approach to a solution.
In this connection, apparatuses for multiple dispensing of washing and cleaning agents have very recently come under scrutiny by product developers. With regard to these apparatuses, a distinction may be made between on the one hand dispensing chambers integrated into the automatic dishwasher or textile washing machine, and on the other hand separate devices independent of the automatic dishwasher or textile washing machine. By means of these apparatuses, which contain several times the quantity of cleaning agent required to carry out a cleaning method, washing- or cleaning-agent portions are automatically or semi-automatically dispensed into the interior of a cleaning machine in the course of multiple successive cleaning processes. For the consumer, the need for manual dispensing for each cleaning or dishwashing cycle is eliminated. Examples of such apparatuses are described in European patent application EP 1 759 624 A2 (Reckitt Benckiser) or in German patent application DE 53 5005 062 479 A1 (BSH Bosch and Siemens Hausgeräte GmbH).
A critical problem with regard to the introduction of such dispensing apparatuses into the interior of dishwashers or washing machines is the thermal instability of heat-sensitive preparation constituents that are to be dispensed. Because, in the context of the dispensing apparatuses described, washing and/or cleaning preparations remain in the water-conveying household appliance for a plurality of washing or cleaning cycles, the activity of enzyme proteins in particular can be significantly reduced at temperatures in dishwashing and washing machines from 70° C. to almost 100° C.
Cartridges for dispensing apparatuses of the kind mentioned above, which protect heat-sensitive ingredients by way of insulating features on the cartridge, are known from the existing art. WO 2008 034697 A1, for example, discloses a multi-chamber cartridge that can be coupled to the door of an automatic dishwasher, the cartridge comprising thermal insulation at least in portions in order to protect heat-sensitive ingredients from excessive heat input from the interior of the automatic dishwasher.
A disadvantage of such insulation solutions is that effective insulation significantly increases the overall size of a cartridge and, depending on the insulation material selected, allows manufacturing costs to rise considerably. In addition, the insulation material must be suitable for withstanding the alternating-temperature and moisture conditions that exist, for example, in the interior of a dishwasher.
Accordingly, it is desirable to furnish a cartridge that can be manufactured economically and simply, and in which heat-sensitive preparations, in particular enzymes, can be stocked in substantially stable fashion in the interior of a water-conveying household appliance.
This object is achieved by a cartridge that is suitable in particular for use in water-conveying household appliances, encompassing an enzyme-containing preparation that contains at least 0.8 wt % of at least one enzyme protein, preferably at least 1.2 wt % of at least one enzyme protein, and has a specific heat capacity cp at 20° C. of less than 3.8 J/(g*K), preferably less than 3.0 J/(g*K), and is stocked in a cartridge or cartridge chamber having an internal volume of between 20 and 500 ml and an average wall thickness of between 0.1 and 2 mm, and the cartridge material has a specific heat capacity cp at 20° C. of between 1 and 2 J/(g*K), preferably between 1.15 and 1.9 J/(g*K), particularly preferably between 1.5 and 1.8 J/(g*K).
Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.